The present invention relates to methods for transplanting devices with a focused beam. More particularly, the invention relates to methods for device transplantation which are capable of repairing and exchanging parts (micro device parts) used in general micro device products such as micro electronic products like large scale integrated circuits, micro optical products, and micro mechanical products.
An example of the prior art has been described in Jp-B-63-25660 (25660-1988). FIG. 3 is a schematic block diagram showing this prior art device. As shown, a gallium liquid metal ion source 100 serves to bombard a sample 200 with an ion beam. The traveling ion beam is deflected by a voltage applied to an electrostatic deflector 105, passes through an objective lens 106, and then is focused on the sample 200. The detector 107 serves to detect, as an intensity signal, secondary electrons ejected from the sample 200 in synchronism with the beam scanning. The intensity signal displayed on a CRT display 400 results in producing an image formed by a scanning ion microscope (hereinafter, abbreviated as a SIM). This image indicates the microminiature structure of the sample 200 at a resolution of about a beam diameter.
When an ion beam bombards the sample, a sputtering phenomenon is brought about, thereby allowing the sample to be etched. And, when the ion beam bombards the sample in a metal-containing gas atmosphere, the metal contained in the gas is deposited on the sample surface for forming a conductive film.
This prior art device is designed to employ those techniques in combination for repairing a wire pattern contained on an integrated circuit. FIG. 4 shows a wiring pattern 10 with a trimming area 30. The ion beam locally bombards the wiring pattern for forming the trimming area 30, thereby electrically disconnecting the pattern. For positioning where the ion beam is bombarded, the SIM image can be used.
FIG. 5 shows a conductive film 7 formed when the ion beam locally bombards in the gas-containing atmosphere according to the prior art. The conductive film 7 serves to electrically connect desired portions of the pattern 10.
The foregoing prior art device makes it possible to trim wiring patterns, which have become unnecessary, and to connect parts, which have become newly necessary, with wiring patterns at a microminiature level, that is, a beam diameter level, thereby being able to exchange and repair the wiring patterns. The newly-formed wiring conductive film, however, has such high resistance that the wiring function cannot be satisfactorily operated. Further, the prior art device does not actually prepare for repairing passive elements and active elements except for the conductive films.